The present disclosure relates to a headrest assembly and more particularly, to active material enabled morphable, positionable, and/or changeable/tunable compliance headrest assemblies.
Headrest assemblies are commonly employed in vehicles and are typically adjustably attached to the seatback. The headrest is in alignment with the back of a seated occupant's head to provide comfort, support, and protection during operation of the vehicle. The padded portion of the headrest that is adapted to provide the support and protection is generally fixedly positioned by the end-user.
Occupants of a vehicle tend to position their seat backs at different angles for comfort. For example, vehicle occupants tend to sit more upright in vehicles with higher seating heights such as vans and so-called sport utility vehicles whereas in cars the occupants tend to be in a more reclined position. The changes in seat back position can move the attached headrest further or closer to the head of the seated occupant. That is, the space between an occupant's head and the headrest can be affected and altered by the seat position. The amount of space between the headrest and the occupant's head can vary, which depending on the magnitude of the space, can be undesirable in certain situations or conditions experienced by the vehicle. For example, in some situations it may be desirable for the headrest to be close to or touching the back of the occupant's head.
Any adjustment of the headrest is typically provided by mechanical actuation, which is generally fixed as a function of the end user adjustment of the headrest and the anthropometry of the seated occupant. Conventional actuators are costly, have a large form factor, and, for those actuators that are electrically actuated, have high power consumption. Further, coupling the output of the actuator to the occupant's needs is not a straightforward process, since a wide variety of occupant sizes must be comprehended in the design.
Accordingly, it is desirable to have a morphable headrest that can be selectively and actively positioned, morphed, manipulated, and/or its compliance changed during use as may be deemed to be desirable for different conditions.